We present a time series of data for temperature, salinity, nitrate, and carbonate chemistry from September 2011 to July 2013 at the University of Washington's Friday Harbor Laboratories. Samples were collected at the Friday Harbor dock and pump house. Seawater conditions at Friday Harbor were high nitrate-low chlorophyll, with average nitrate and pCO 2 concentrations of 25 6 5 lmol L 21 and 700 6 103 latm (pH 7.80 6 0.06). Transient decreases in surface water nitrate and pCO 2 corresponded with the timing of a spring bloom (April through June). The high nitrate and pCO 2 originate from the high values for these parameters in the source waters to the Salish Sea from the California Undercurrent (CU). These properties are due to natural aerobic respiration in the region where the CU originates, which is the oxygen minimum zone in the eastern tropical North Pacific. Alkalinity varies little so the increase in pCO 2 is due to inputs of dissolved inorganic carbon (DIC). This increase in DIC can come from both natural aerobic respiration within the ocean and input of anthropogenic CO 2 from the atmosphere when the water was last at the sea surface. We calculated that the anthropogenic "ocean acidification" contribution to DIC in the source waters of the CU was 36 lmol L 21 . This contribution ranged from 13% to 22% of the total increase in DIC, depending on which stoichiometry was used for C/O 2 ratio (Redfield vs. Hedges). The remaining increase in DIC was due to natural aerobic respiration.The surface ocean is growing more acidic due to uptake of anthropogenic CO 2 (Brewer 2000;Caldeira and Wickett 2003). As a result, marine ecosystems, the services they provide for humanity, and the societies they support are at risk. Impacts of ocean acidification (OA) will be felt across all ocean basins but are intensified in many coastal areas due to natural processes like upwelling, freshwater input and local respiration (Duarte et al. 2013). Over time, as atmospheric CO 2 continues to increase, the biological consequences of OA can propagate through marine foods webs, from the lowest to the highest levels, including species valued as food resources for humans (Fabry et al. 2008;Hall-Spencer et al. 2008;Portner 2008).In urbanized coastal regions and estuaries there are three sources for acidification of the ocean. One is natural and two are anthropogenic. In all three cases the increases in pCO 2 are due to increases in dissolved inorganic carbon (DIC) rather than decreases in alkalinity. The increase in DIC is calculated from the increasing pCO 2 at constant alkalinity.1. Classic "ocean acidification" is due to the increase in DIC resulting from equilibration of surface seawater with increasing CO 2 in the atmosphere (where it is steadily increasing) (e.g., Feely et al. 2004;Sabine et al. 2004

A yeast two-hybrid screen was utilized to identify novel Smad 3 binding proteins expressed in developing mouse orofacial tissue. Three proteins (Erbin, Par-3, and Dishevelled) were identified that share several similar structural and functional characteristics. Each contains at least one PDZ domain and all have been demonstrated to play a role in the establishment and maintenance of cell polarity. In GST (glutathione S-transferase) pull-down assays, Erbin, Par-3, and Dishevelled bound strongly to the isolated MH2 domain of Smad 3, with weaker binding to a full-length Smad 3 protein. Failure of Erbin, Par-3, and Dishevelled to bind to a Smad 3 mutant protein that was missing the MH2 domain confirms that the binding site resides within the MH2 domain. Erbin, Par-3, and Dishevelled also interacted with the MH2 domains of other Smads, suggesting broad Smad binding specificity. Dishevelled and Erbin mutant proteins, in which the PDZ domain was removed, still retained their ability to bind Smad 3, albeit with lower affinity. While transforming growth factor beta (TGFbeta) has been suggested to alter cell polarity through a Smad-independent mechanism involving activation of members of the RhoA family of GTP binding proteins, the observation that Smads can directly interact with proteins involved in cell polarity, as shown in the present report, suggests an additional means by which TGFbeta could alter cell polarity via a Smad-dependent signaling mechanism.

This study is the first to report a unique genetic strategy to permanently label mammalian neural crest cells (NCC) with a fluorescent marker, selectively isolate the labeled NCC or their derivatives during murine ontogenesis by laser capture microdissection (LCM), and prepare molecular components, such as RNA, for selective gene expression analyses. Through utilization of a Cre recombinase/loxP system, a genetic strategy that has been used repeatedly to achieve tissue-specific activation of reporter transgenes in mice, a novel two-component mouse model was created in which neural crest cells (and their progeny) are indelibly marked throughout the pre- and postnatal lifespan of the organism. To generate this mouse model, a Wnt1-Cre transgenic line was crossed with a mouse line expressing a conditional reporter transgene ("floxed" enhanced green fluorescent protein). Resulting offspring, expressing both the Wnt1-Cre and "floxed" EGFP alleles, demonstrated EGFP expression in the NCC and all of their derivatives throughout embryonic, postnatal, and adult stages. In the present study, EGFP-labeled cranial NCC from the first branchial arch of gestational day 9.5 murine embryos were visualized in frozen tissue sections and isolated by LCM under epifluorescence optics. RNA was extracted from "captured" cells and amplified by double-stranded cDNA synthesis and in vitro transcription. Amplified mRNA samples from "captured" cells were evaluated by TaqMan quantitative, real-time PCR for the expression of a panel of NCC gene markers. The molecular genetic strategy delineated in this report will facilitate future embryo-genomic and -proteomic analyses of mammalian NCC that will serve to further our understanding of these pluripotent embryonic progenitor cells.

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Rapid changes, including warming and freshening, are occurring in coastal marine ecosystems worldwide. These environmental changes have the potential to alter ecosystem energetics by influencing availability of food sources and organism physiology. We investigated the influence of oceanographic variability on food availability and quality to benthic and pelagic suspension-feeders using detailed observations of phytoplankton, particulate organic matter (POM) detritus, and diverse biomarkers (fatty acids and carbon, nitrogen, and sulfur stable isotopes) along a salinity gradient in the San Juan Archipelago, Washington, U.S.A. We tested the hypothesis that freshwater input from riverine discharge would cause significant changes to oceanographic conditions and reduce food quality (indicated by essential fatty acids; EFA), owing to greater contribution of terrestrial organic matter. Contrary to our expectations, availability of high-quality marine-derived POM increased with freshwater input (reduced salinity). Phytoplankton biomass and biomarker composition responded to oceanographic change similarly across tidal and seasonal scales. Using a meta-analysis spanning a range of spatial and temporal scales, we found that chlorophyll a, temperature, dissolved oxygen (DO) and pH were consistently and significantly higher at reduced salinity. The increase of DO and pH corresponding to higher phytoplankton biomass in low salinity water signifies an important feedback of biological activity on seawater chemistry. This analysis supports the use of salinity as an indicator of processes controlling food availability and oceanographic conditions in this region. Collectively, these results highlight the importance of ecosystem connectivity in coastal environments and produce hypotheses for expected changes related to altered river discharge dynamics.